The Revo LDS triangulation-based rangefinder is not available for purchase separately, but getting a Neato XV-11 is still much cheaper than other time-of-flight based laser rangefinders. Of course, the Hokuyo/SICK laser rangefinders are more accurate, but the cost is quite prohibitive for most hobbyists.

If you just want 360 degrees of distance, and can afford slow speed, a Sharp IR rangefinder on a servo could give you that data for less than $30.